Effect of Irrigation Regime and Natural Soil Conditioner on Crop Productivity in Sandy Soil

A FIELD experiment was conducted in sandy soil in Ismailia Governorate, Egypt, during two successive winter and summer seasons cultivated with lupine and sesame, respectively. The aim of this study was to evaluate the effects of three different water regimes (i.e., 0.8, 1.0, and 1.2 accumulative pan evaporation) and applied different rates (3, 4.5, and 6 ton fed^-1) of bentonite as mineral soil conditioner on crop productivity of both lupine and sesame crops under drip irrigation system. Total content of mineral nutrients of both tested plants were taken in consideration. [e1] Results indicated that, the highest actual evapotranspiration (ETa) was recorded under 1.2 accumulative pan evaporation treatment, for both lupine and sesame cropping system, while the lowest one was recorded under 0.8 accumulative pan evaporation. Also, applied 6.0 ton fed^-1 bentonite was recorded lowest values of ETa in both seasons, whereas the highest value was obtained under zero ton fed^-1 bentonite for the same respective crops. In addition, under Ismailia condition it could be concluded that pan evaporation and Hargreaves equations are more suitable to use for scheduling irrigation for lupine and sesame crops compared with the other equations. [e2] On the other hand, lupine and sesame yields (straw and grain/or seeds) along with total content of macronutrients (N, P and K) increased significantly under the irrigation treatment of  1.2 accumulative pan evaporation in present of 6.0 ton fed^-1 bentonite mineral soil conditioner as compared to other treatments.